Typically, graphing functions is a way of studying the behaviors of the function as the independent variable changes. The most common independent variable in real life applications is time. For example,In physics, you can explore motion by graphing distance over time. An interesting application for your students might be to look at the graph of the spread of a virus. When real life data can be approximated with algebraic functions, you gain the ability for prediction. For example, you could predict the number of a certain species of animal on the endangered species list if you fit a function to the data collected so far. It is best to start with linear functions when introducing functions. Check out NCTM Illuminations for some lesson ideas.

You should learn about it because it’ll help you in real life.